Ovalization

[Eugene Moore]

There is a torsional element involved, but it is not the primary failure mechanism.
The direction of the haul is at an angle to the casting plane.
If the guides are rotated in 90 degrees this increases the leverage of the haul against the blank, increasing the stress load on the ferrule. If the guides are rotated outward the haul direction decreases the leverage by attempting to pull the guide into the blank rather than away from it decreasing the ultimate load on the female ferrule. The main failure was total flexural load and splitting of the female ferrule end up toward the tip. Notice the wraps are split in a straight line and the wrap end exposed outward. A sign of over load of the inside of the cylinder. Paul also noted the failure was in line with the casting plane with the guides rotated outward I assume 45 degrees. My suggestion of 60 degrees was to take advantge of this and will reduce stress only slightly.
I've seen several failures of this nature when the rod was overloaded, though this is the first seen during a casting stroke on a fly rod. Most are the result of fighting fish on a line too heavy for the rod. Another reason I may think twice about Paul's handshake.
Just joking. He's probably a very pleasant individual with a very powerful arm.
Sorry for restating your reply Paul we were typing at the same time.

[Hal Jordan]

He's probably a very pleasant individual with a very powerful arm.

Actually he has kind of girly arms.

[Paul Arden]

Big girly arms.

[VGB]

Eugene/Paul

Thank you for the explanations, it makes sense. The reason I asked for a clarification was because I thought that the load at the ferrule might be reduced with a split load path caused by rotation. However, because of the lock ups in normal orientation, it appears that you will never get the single load path case.

Do the horizontal breakages happen at the 1st time of using the rod or after you have been using it for a while?

regards

Vince

[Paul Arden]

Horizontal breakages for me sometimes happen first cast, only once have they not occurred in the first ten minutes. These ferrule cracks generally break at around 12 months for me. I've never got more that 12 months out of a distance casting rod.

[VGB]

Thanks Paul

So horizontal breaks appear to be a kind of "infant mortality" that I would guess are due to either manufacturing faults or you using the rod beyond its design limits.

Ferrule cracking is probably fatigue based due to large cyclic loads. I would suspect that not man manufacturers go through that sort of testing like this:

http://www.youtube.com/watch?v=TH9k9fWaFrs

Keep on cooking

Vince

[Hal Jordan]

Big girly arms.

Sure - if it makes you feel better. :p

The ferrule cracks that appear to be fatigue based - have you looked at the Dan Craft blanks? They have a ferrule design that doesn't require wrapping of the ferrules. It would be interesting to see if these have a longer life in your case.

[Torsten]

Hi Gordy,

of course I've meant transverse stress as well, these can be a result of bending and torsion. And for me it seems to be unlikely that a typical blank is able handle a high stress in that direction (without reinforcement).

--

Sure we have a scrim, but as far as I know this is only a thin sheet of glass / graphite ?

Is torsion tested at all ? I've seen in those YouTube clips only static bending tests.

--

Paul, do you have some more pictures of the TCR? Looks like there are no reinforcement fibers.

I've checked my #4 XP and this ferrule has indeed no reinforcement. On the other hand I have a low price #7 rod, which has plenty of graphite in 90° direction wrapped around the ferrule.
For my own builds I'm wrapping the entire length of the ferrule with size A thread and I've not had so far problems there (I'm doing this also because I've less trouble with loose sections).

Bye ..
Torsten

[VGB]

Torsten

As far as I can make out through the sales blurb, it is carbon fibre scrim on the TCX. I am not aware of any torsion testing or declared limitations on blanks.

regards

Vince

[Paul Arden]

Sorry no more pictures here at the moment. Considering what it goes through I think they do extremely well - I wish lines lasted that long! It's generally cheaper to replace a section. A bust section after twelve months of serious distance casting I think shows excellent design strength. Most people will never break it. Jerry talked to Marc about strengthening that ferrule, but for what, half a dozen people?

I have no problems there. I've killed cars quicker. Where I do have a problem is when I break a rod in less than five minutes.

Cheers, Paul

[Torsten]

Hi Paul,

I think you're right. It's not easy to say if ferrule reinforcement makes sense for them. For my own builds I'd make it - because I have a better feel, even if that break never happens (repairing costs time and nerves).
Another question is also, how much weight and work an additional sheet of carbon at these spots costs.

Bye,
Torsten

[Torsten]

Here is a picture from Theo Matschewsky's site, that shows what I mean:

[Eugene Moore]

If you have the ear of Sage and are looking for a fix that may be done for all anglers.
A slight guide adjustment will help.
Distance from tip to guides
4.2 9.0 14.5 20.8 27.9 36.0 45.2 55.7 67.7 81.3
This will position the stripper guide just above the ferrule wrap increasing the stiffness of the ferrule and reducing the leverage against the haul. Shouldn't harm any other aspect of the rod.
If the rod can more efficiently handle the torque your distance potential will increase.

[VGB]

Adding additional weight in the top section will have a performance effect that for fishing may be trivial but for competition distance may be important. For distance Eugene's suggestion is worth a shot.

On the plus side for composites, the S-N (strength to cycles) curve is fairly flat so that any performance drop off is rapid at the point of failure, rather than progressively through life. So there is no need to keep a pristine rod for competition.

[gordonjudd]

This will position the stripper guide just above the ferrule wrap increasing the stiffness of the ferrule and reducing the leverage against the haul.

Eugene,
I do not understand what you mean by "reducing the leverage." Does it have something to do with decreasing the perpendicular distance from the inside of the guide to the center of the rod's neutral bending axis when it is bent so it would reduce some sort of twisting moment? I do not see why moving the stripper down towards the end of the ferrule would have any effect on that distance.

Maybe a simple drawing of some sort would illustrate what you are talking about, for those like me who are verbally challenged.

Gordy